Laser comb: simulations of pre-modulated e- beams at the photocathode of a high brightness rf photoinjector

A density modulated electron beam generated at the photocathode of a radio-frequency electron gun evolves within an accelerator towards a homogenous beam but with an energy modulation. The density modulation is changed into energy modulation. This energy distribution can be exploited to restore the initial density profile, called comb beam, with a proper rf phase of the accelerating cavities and by adding a proper compressor. The comb beam at the cathode is generated driving the photocathode by the relative laser pulse train. This laser pulse is obtained with a shaping device inserted into the laser system. The dynamics is studied within the SPARC system with the PARMELA code

A possible THz Radiation Source with a Train of Short Pulses in the SPARC high brightness photoinjector

A radiofrequency electron gun followed by a compressor can generate trains of terahertz sub- picosecond electron pulses by illuminating the photocathode with a comb laser pulse. Any radiation process which does not change the electron distribution can be used to study the coherent spectrum of radiation emitted by a comb electron bunch. The coherent part of the spectrum is strongly enhanced by its N2 dependence, where N is the number of particles in the bunch, being interesting both as possible source of Far-Infrared Radiation (FIR) and as diagnostic tool of the bunch structure. A feasibility study for a possible experiment at SPARC to be realized with the addition of a dedicated magnetic chicane is discussed. An optimization study of a magnetic chicane with a negative and variable R56 is studied, together with a set of parameters relative to the SPARC machine with the intent of demonstrating the feasibility of this experiment. The dynamics is studied within the SPARC system with the PARMELA code

Design Study of a Dedicated Beamline for THz Radiation Generation at the SPARC Linac

A feasibility study for a dedicated beamline for a THz radiation source at SPARC is discussed here. Two phases are foreseen for the THz radiation generation beamline. In the first phase of operation the SPARC electron beam will be transported through a dogleg and then delivered to a THz radiator, allowing a full characterization of the THz radiation. In the second phase a magnetic compressor with negative R56 will be implemented in the dogleg, allowing exotic experiments with THz radiation produced by comb beams. A radiofrequency electron gun followed by a compressor can generate trains of THz sub-picosecond electron pulses by illuminating the photocathode with a comb laser pulse. This structure of the beam can be used to produce coherent radiation. The quality of the coherent spectrum emitted by a comb beam is tightly connected to the electron micro-bunches lengths and to micro-pulses inter-distance

The future prospects of muon colliders and neutrino factories

The potential of muon beams for high energy physics applications is described along with the challenges of producing high quality muon beams. Two proposed approaches for delivering high intensity muon beams, a proton driver source and a positron driver source, are described and compared. The proton driver concepts are based on the studies from the Muon Accelerator Program (MAP). The MAP effort focused on a path to deliver muon-based facilities, ranging from neutrino factories to muon colliders, that could span research needs at both the intensity and energy frontiers. The Low EMittance Muon Accelerator (LEMMA) concept, which uses a positron-driven source, provides an attractive path to very high energy lepton colliders with improved particle backgrounds. The recent study of a 14 TeV muon collider in the LHC tunnel, which could leverage the existing CERN injectors and infrastructure and provide physics reach comparable to the 100 TeV FCC-hh, at lower cost and with cleaner physics conditions, is also discussed. The present status of the design and R&D efforts towards each of these sources is described. A summary of important R&D required to establish a facility path for each concept is also presented.Comment: 29 pages, 17 figure

Characterisation of the Beamstrahlung radiation at FCC-ee

Beamstrahlung is a dominant effect in the beam dynamics of the high luminosity next-generation lepton collider FCC-ee. We characterize the beamstrahlung radiation for the beam parameters at the four working energies, from the Z-pole to the $t\bar{t}$ threshold, and present the effect of this radiation in the Machine-Detector-Interface region. We discuss the conceptual need for a photon dump due to the high power produced, which is in the order of hundreds of kilowatts. We also discuss the detector induced backgrounds due to the incoherent $e^+e^-$ pairs produced by the interaction of the beamstrahlung photons at the IP.Comment: Submitted to Physical Review Accelerators and Beam

LC-MS/MS Method Applied to the Detection and Quantification of Ursodeoxycholic Acid Related Substances in Raw Material and Pharmaceutical Formulation

Abstract: Objective: To develop a highly sensitive LC-MS/MS (liquid chromatography-mass spectrometry/mass spectrometry)method applied to the detection and quantitation of UDCA (ursodeoxycholic acid) related substances such as CA (cholic acid), DCA(deoxycholic acid), CDCA (chenodeoxycholic acid) and LCA (lithocholic acid) in raw material and pharmaceutical formulation.Methods: The method was validated for specificity, linearity, accuracy, precision, robustness. A triple quadrupole mass detector wasemployed, equipped with an ESI (electrospray ionization) source operated in the negative ion mode. The chromatographic systemconsisted of a Symmetry C18 column (150 mm × 4.6 mm, id; particle size 5 µm) and methanol-acetonitrile-ammonium acetate (pH 7.6;10 mM) (40:40:20, v/v/v) as the mobile phase. The chromatographic conditions were 25 uL injection volume, flow rate of 0.4 mL/minand column temperature set at 35 °C. Key findings: The method requires a minimum sample amount and presents very low LOD(limits of detection) for CA (0.29 ng/mL), DCA (0.59 ng/mL), CDCA (0.13 ng/mL) and LCA (0.44 ng/mL) in comparison to LCmethods coupled to different detectors like UV (ultraviolet), fluorescence and refractive index. Conclusions: The developed andvalidated LC-MS/MS method for the determination of UDCA and related substances in raw material and in a suspension wasadvantageous since it required a minimum sample amount. In turn, it could be used as a stability indicating method.Fil: Boscolo, Oriana. Universidad de Buenos Aires. Facultad de Farmacia y Bioquímica. Departamento de Tecnología Farmacéutica; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Houssay; ArgentinaFil: Flor, Sabrina Andrea. Universidad de Buenos Aires. Facultad de Farmacia y Bioquímica. Departamento de Química Analítica y Fisicoquímica. Cátedra de Química Analítica; Argentina. Universidad de Buenos Aires. Facultad de Farmacia y Bioquímica. Departamento de Tecnología Farmacéutica; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Houssay; ArgentinaFil: Dobrecky Ceciclia. Universidad de Buenos Aires. Facultad de Farmacia y Bioquímica. Departamento de Tecnología Farmacéutica; Argentina. Universidad de Buenos Aires. Facultad de Farmacia y Bioquímica. Departamento de Farmacología; ArgentinaFil: Martinefski, Manuela Romina. Universidad de Buenos Aires. Facultad de Farmacia y Bioquímica. Departamento de Química Analítica y Fisicoquímica. Cátedra de Química Analítica; Argentina. Universidad de Buenos Aires. Facultad de Farmacia y Bioquímica. Departamento de Tecnología Farmacéutica; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Houssay; ArgentinaFil: Tripodi, Valeria Paula. Universidad de Buenos Aires. Facultad de Farmacia y Bioquímica. Departamento de Tecnología Farmacéutica; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Houssay; ArgentinaFil: Lucangioli, Silvia Edith. Universidad de Buenos Aires. Facultad de Farmacia y Bioquímica. Departamento de Tecnología Farmacéutica; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Houssay; Argentin

Recent Advances and Novel Ideas for High Brightness Electron Beam Production Based on Photo-Injectors

Photo-injectors beam physics remains a fruitful and exciting field of research. New ideas have been recently proposed to achieve ultra-high brightness beams, as particularly needed in SASE-FEL experiments, and to produce flat beams as required in linear colliders. An overview of recent advancements in photo-injector beam physics is reported in this paper

Machine detector interface for the e+e−e^+e^- future circular collider

The international Future Circular Collider (FCC) study aims at a design of $pp$, $e^+e^-$, $ep$ colliders to be built in a new 100 km tunnel in the Geneva region. The $e^+e^-$ collider (FCC-ee) has a centre of mass energy range between 90 (Z-pole) and 375 GeV (tt_bar). To reach such unprecedented energies and luminosities, the design of the interaction region is crucial. The crab-waist collision scheme has been chosen for the design and it will be compatible with all beam energies. In this paper we will describe the machine detector interface layout including the solenoid compensation scheme. We will describe how this layout fulfills all the requirements set by the parameters table and by the physical constraints. We will summarize the studies of the impact of the synchrotron radiation, the analysis of trapped modes and of the backgrounds induced by single beam and luminosity effects giving an estimate of the losses in the interaction region and in the detector.Comment: 6 pages, 7 figures, 62th ICFA ABDW on High Luminosity Circular $e^+e^-$ Colliders, eeFACT2018, Hong Kong, Chin

Biochemical and thermodynamic characteristics of a new serine protease from Mucor subtilissimus URM 4133

A protease from the fungus Mucor subtilissimus URM 4133, capable of producing bioactive peptides from goat casein, was purified. SDS-PAGE and zymography showed a molecular mass of 30 kDa. The enzyme was active and stable in a wide pH range (6.0–10.5) and (5.0–10.5), respectively. Optimum temperature was at 45–50 °C and stability was above 80 % (40 °C/2 h). Activity was not influenced by ions or organic substances (Triton, Tween, SDS and DMSO), but was completely inhibited by PMSF, suggesting that it belongs to the serine protease family. The Km and Vmax were 2.35 mg azocasein.mL-1 and 333.33 U.mg protein-1, respectively. Thermodynamic parameters of irreversible denaturation (40–60 °C) were enthalpy 123.63 – 123.46 kJ.mol-1, entropy 120.24–122.28 kJ.mol-1 and Gibbs free energy 85.97 – 82.45 kJ.mol-1. Any peptide sequences compatible with this protease were found after analysis by MALDI-TOF, which suggests that it is a new serine protease.info:eu-repo/semantics/publishedVersio